Cognex Corporation, Natick, MA, offers the In-Sight® 1820 vision-based wafer pre-aligner. Utilizing proprietary Cognex Notch-MaxTM alignment technology, the 1820 vision system provides precise non-contact measurement of wafer position and orientation in less than half a second. Mechanical pre-aligners must typically spin wafers for several seconds.
NotchMax aligns wafers with a center position accuracy of ± 15μm and an orientation accuracy of ± 0.05 degrees. More accurate pre-alignment saves fine alignment steps inside a process tool, boosting throughput. The system has the ability to handle changing wafer sizes and types with simple parameter changes, and its non-contact design minimizes wafer handling and potential wafer damage.